Reconsider the accompanying sample data on expense ratio (%) for large-cap growth mutual funds first introduced in Exercise 1.53.

A normal probability plot shows a reasonably linear pattern.
a. Is there compelling evidence for concluding that the population mean expense ratio exceeds 1%? Carry out a test of the relevant hypotheses using a significance level of .01.
b. Referring back to (a), describe in context type I and II errors and say which error you might have made in reaching your conclusion. The source from which the data was obtained reported that μ = 1.33 for the population of all 762 such funds. So did you actually commit an error in reaching your conclusion?
c. Supposing that σ = .5, determine and interpret the power of the test in (a) for the actual value of m stated in (b).

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0.52 1.06 1.26 2.17 1.55 0.99 1.10 1.07 1.81 2.0 0.91 0.79 1.39 0.62 1.52 1.02 1.10 1.78 1.01 1.15